A woman out of breath (6)
I believe the answer is:
bertha
'a woman' is the definition.
'out of breath' is the wordplay.
'out of' is an anagram indicator.
'breath' anagrammed gives 'BERTHA'.
(Other definitions for bertha that I've seen before include "Breath (anag) - girl's name" , "Female name; Big -, World War one German howitzer" , "The bar (anag.)" , "43-ton German howitzer, Big _____" , "Big girl" .)